Dietary (conjugated) folates must be digested to simple folates by an intestinal enzyme system. Our studies examine the digestion and absorption of conjugated folates in man by a perfusion technique. Additionally, we are investigating the characteristics of the intestinal enzyme system for folate digestion in specimens of human jejunum obtained during surgery. A monkey model is used to study the effects of chronic alcoholic liver disease on intestinal absorption and hepatic metabolism of folates.